A productive workforce is a key objective of public economic policy. Recent empirical work suggests that increasing individual participation in sports and exercise can be a major force for achieving this goal. The productivity gains and related increase in earnings come on top of the already well-documented public health effects that have so far provided the rationale for the major national and international campaigns to increase individual physical activity. The deciding issue for government policy is whether there are externalities, information asymmetries, or other reasons that lead individuals to decide on activity levels that are too low from a broader social perspective.